1. Field of the Invention
The present invention relates generally to an image compression apparatus and a method of compressing the image.
2. Description of the Related Art
As low luminance noise is typically included in a photograph or video image captured in a low luminance environment, compression efficiency and image quality suffer even when the photograph or video image are compressed.
A system in which a low luminance noise cancellation algorithm is implemented, e.g. an image compression system equipped with a camera, has been suggested to cancel the low luminance noise before a photograph or video image is compressed. To this end, a camera image sensor has a function of selectively detecting a low luminance pixel.
FIG. 1 is a block diagram of a conventional image compression apparatus having a low luminance noise cancellation function. Referring to FIG. 1, the conventional image compression apparatus includes an image capturer 10 for capturing an input image, a low luminance noise canceller 20 for canceling low luminance noise from the input image, and an image compressor 30 for compressing a low luminance noise cancelled image. Since an image output from the image capturer 10 is input to the low luminance noise canceller 20, every image is input to the low luminance noise canceller 20. As a result, a low luminance noise cancellation process is performed for every image. As described above, conventionally, the low luminance noise cancellation process is performed for every image in the image compression apparatus.
However, the low luminance noise cancellation algorithm requires a great amount of computation and is difficult to be applied to all photographs and video images in real-time. In addition, low luminance noise significantly affects the image quality as the number of pixels of a camera increases. Further, the low luminance noise cancellation algorithm is difficult to be applied to a low-performance processor employed in a cellular phone, and may be a reason of excessive power consumption.